Electrical wire lead connector



March 22, 1966 B, HASKELL 3,242,457

ELECTRICAL WIRE LEAD CONNECTOR Filed Jan. 1'?, 1963 FIGA lo 16 l2 FIG,5

BORIS HASKELL ATTORNEYS United States Patent Oce 3,242,457 Patented Mar. 22, 1966 3,242,457 ELECTRICAL WIRE LEAD CNNECTR Boris Haskell, 3715 Underwood St., Chevy Chase, hdd. Filied Jan. i7, 1963, Ser. No. 252,163 S Claims. {CL 339-95) The present invention relates to electrical connectors, `and particurlarly to terminal and splice type connectors for wire leads, such as are used for battery and electrical equipment terminals, for terminal blocks and panels, for connecting wire leads to plugs, sockets, and each other, and for lead-in connector panels and boards.

The usual terminal type connector employs a threaded screw set in a threaded hole in a panel, or a threaded nut engaged on a threaded part projecting from a panel. In each instance a wire lead is connected to such terminal either by means of a connector lug seated on the stem of the screw or post, or by winding the end of the lead around said stern, whereupon the two threaded elements are tightened together clamping the wire lead. These terminal connectors suffer from certain disadvantages, amongst which are their tendency to loosen under vibration or to loosen when the lead is pulled. These structures, While reasonably effective and inexpensive fail to provide an effective jam union and friction interface between the wire lead and connector parts to insure against the aforementioned disadvantages.

The present invention overcomes the foregoing disadvantages of these threaded types of connectors, while still retaining the important features of being inexpensive, durable, and easy to use. Broadly, the present invention provides a connector of two parts or elements, one being a base plate and the other being a cap cooperating therewith. These two elements are rotatably connected to each other in surface engagement, and are adapted upon relative rotation to sandwich a wire lead therebetween, and thereby electrically connect the lead either to a member upon which the connector is mounted, or to another lead, either soldered to the connector or similarly secured to the connector.

As distinguished from most other connectors of this general category, an important feature of this invention is that the two connector parts are adapted to sandwich a wire lead therebetween by circumambiently compress the wire lead over a portion of its axial length, thus creating a jam union between the two connector parts and the wire lead, so as to render the union between the connector and the wire secure against unintentional loosening through vibration or other causes.

To this end, the base plate is provided on one surface with a tapering groove which tapers both in depth and transverse dimension. A at cap is rotationally mounted on said base in surface engagement therewith, and in such a position that as the cap is rotated its leading edge advances along said groove, thereby covering more and more of said groove toward its apex as the cap is rotated in one direction, while exposing more and more of said groove toward its base as the cap is rotated in the opposite direction.

When the end of a wire lead is laid in the groove from the apex toward the base, at some point along the axis of the groove the wire will begin to protrude out of the groove and above the surface of the base plate. The cap is rotated toward the apex of the groove to cover the groove until the leading edge of the cap engages the wire lead at its point of protrusion from the groove. On continued forceful rotation of the cap, its leading edge bites into the wire lead, and forces it a short distance along the groove into a smaller cross-sectional area portion of the groove, thereby signicantly cincturing or circumambiently neclzing the wire lead at the point of contact with the leading edge of the cap member. Also the Wire lead is compressed to a lesser degree .along the length immediately following the cincture, as it is forced into the narrowing confines of the groove by the overlying surface of that portion of the cap following the leading edge. Because of the maximum necking down of the wire at the cincture, the lead cannot be dislodged from the connector Without the cap member being backed off. Also, because of the compression of the wire over a portion of its axial length between the base plate and cap, a jam union is effected requiring a considerable amount of force to loosen the connector from the wire,

It is accordingly one object of the present invention to provide a wire lead connector of the terminal or splice type.

Another object of the present invention is to provide such a connector comprised of two parts, a base and a cap, rotatively coupled together in surface interengagement.

Another object of the present invention is to provide such a connector which clamps a wire lead between said base and cap with a circumambient necking down or compression of the wire aiong a portion of the axial length of the wire.

Still another object of the present invention is to provide such a connector which additionally effects a maximum cincture at one point along said length of compression.

Other objects and advantages of the invention will become apparent to those skilled in the art from a consideration of the following description of several detailed exemplary specific embodiments thereof, had in conjunction with the accompanying drawings, in which like numerals refer to like or corresponding parts, and wherein:

FIG. l is a perspective view of a single lead terminal connector embodying the present invention;

FIG. 2 is a top plan view of the embodiment of the invention shown in FIG. l;

FIG. 3 is a cross-sectional view of the embodiment of the invention shown in FIG. l, taken along line 3 3 of FIG. 2;

FIG 4 is a cross-sectional View of the embodiment of the invention shown in FIG. l, taken along line 4 4 of FIG. 2;

FIG. 5 is a cross-sectional view of the embodiment of the invention shown in FIG. l, and is similar to FIG. 3, but shows a wire lead affixed to the connector.

FIG. 6 is a top plan view of the terminal connector shown in FIG. 5;

FIG. 7 is a top plan View of a two lead terminal connector similar in form to the embodiment of FIGS. 1 6;

FIG 8 is a perspective view of another embodiment of the present invention; and

FIG. 9 is a perspective View of still another embodiment of the present invention.

The single lead terminal type connector illustrated in FIGS. 1 6 comprises a base plate 10, upon which is mounted the cap 11. Cap 11 is rotatably connected to the base 10 by means of a lug 13 depending from an eccentric point on the cap 11, and passing through an aperture in the base 10. The end of the lug is swaged out at 17 into an enlarged head seated in recess 18 on the underside of base 10, thereby rotatably uniting the cap to the base. The upper surface of base llt)` is provided -with a groove 12 which tapers both in depth and breadth from a maximum at its base 12a to a minimum at its apex 12b. This groove may be V shaped in crosssection, as shown, or circular or arcuate if desired, or other suitable shape capable of serving the purposes hereinafter described.

The eccentric pivot 13 for the cap 11 is located on the cap and base at -a position adapted to permit the cap 11 to cover and uncover the slot or `groove 12 as the cap is pivoted. For this purpose, the cap is preferably elongated in shape, such as oval, with the pivot 13 located adjacent one end of the major axis on the cap, and to one side of the groove 12 adjacent its base 12a on the plate 10. Of course the cap 11 may also be round instead of oval, or semicircular, or semioval, or an elongate rectangle, or otherwise contoured to provide a leading edge 15 adapted to perform the function of covering and uncovering, or passing over the groove 12 from its base 12a to its apex 12b.

With the cap 11 pivoted to a position to open or expose the groove 12, the end of a wire lead 14 stripped of insulation is laid in the groove 12 over its apex 12b toward its base 12a, and the cap 11 is pivoted, as by means of a screw driver in blade solt 11a, over the groove until the leading edge 15 of the cap 11 abuts the wire lead 14 at that point along the groove where the lead begins to project out of the groove above the upper surface of the base plate 10. This point along the groove will of course vary depend-ing on the diameter of the wire 14.

Continued forceful pivoting of cap 11 toward the apex 12b of groove 12 effects several operations on the wire 14 in the area of portion 16. First the leading edge 15 of the cap cams the portion 16 of the wire down into the groove 12, causing it to deform into the shape of the groove as it is forced toward the bottom of the groove. At the same time, the leading edge 15 bites into and notches the upper surface of the wire lead 14, as shown in FIG. 5. Continued pivoting of cap 11 toward apex 12b causes the wire 14 to slide slightly along the groove 12, resulting, not only in further co-mpression at the point of contact with leading edge 15 of cap 11, but also causing compression of the wire in the area of portion 16 just behind the leading edge 15 under the cap 11, as this portion of the wire is drawn into that section of the groove 12 where initial compression was effected by edge 15. This entire compression of the wire is circumambient, being shown in the vertical plane in FIG. 5, and in the horizontal plane in FIG. 6.

This compression of the wire 14 causes a ow of wire metal from the area of compression into the adjacent uncompressed or unconned portions of the wire, resulting in a circumambient necking down of the wire in the area 16. Maximum compression of the Wire is had at the leading edge 15, causing a cincture of the wire at this point, thereby preventing the Wire from sliding out of the bite between the base 1d and the cap 11. The further area of wire compression along its axial length under the cap 11 and immediately behind the leading edge 15, effects a jam lock on the cap 11, restraining it against loosening its grip on the wire by back-off from vibration and like causes. Also, the reaction force of the compressed wire tends to take up any play in the t of the cap 11 on the base 10 and effects a frictional engagement between these two surfaces.

The possibility of shearing the wire with the leading edge 15 of cap 11 is minimized by two factors. The first is the fact that because of the slope of groove 12 relative to the plane of movement of cap 11, the line of shearing force is not orthogonal to the Wire, but is at an acute angle thereto, thereby greatly increasing the length of the line of shear over that of an orthogonal shear plane. The second factor is the compression along the axial length of the wire in the area 16, `greatly increasing the force required to rotate cap 11 in the direction of increased wire compression above that force which would be required with merely a single line of circumferential compression. This protection against shear is particularly important when connecting very thin Wire leads and multistrand wire.

The foregoing embodiment of the invention providing a single lead connection, is intended as a treminal connector, wherein base plate would be connected by solder or the like to another lead or electrical component. For this purpose, base plate 10 would be fabricated of a conductive metal, while cap 11 could be of metal or other suitable material. Also, this embodiment could be used as a simple splice by twisting the ends of two leads together and inserting the united wires in the groove 12. For this purpose both the plate 10 and cap 11 could be formed of a hard plastic or other insulating material.

A second embodiment of the invention is shown in FIG. 7, for connecting or splicing two leads by means of a dual terminal assembly of the general type above described. Here the base plate 20 is formed with two tapered V grooves 22, each with its respective cap member 21 and 24 rotatively coupled at 23 and 26 to the base plate 20. In this instance a rst wire lead is clamped in groove 22 by cap 21 in the same manner as described with repsect to FIGS. l-6, and a second wire lead is similarly clamped in groove 25 by means of cap 24. With the base plate 20 formed of conducting material, these two leads are thereby electrically coupled to each other. Obviously any number of terminal assemblies could be formed on one base plate, and if desired any number of individual single terminal or multiple terminal assemblies could be mounted in an insulating housing or on a panel to form a multiple terminal block.

Still another embodiment of the invention is shown in FIG. 8. There is here shown a rectilinear single terminal assembly. The base plate 30 is formed with two upstanding ears 31 and 32 mounting a threaded lead screw 36 having a cooperating threaded slider block 33 thereon. A tapered V groove 34 similar to V grooves 12, 22, and 25 is formed in the upper surface of the base plate 36 for receiving the end of a wire lead. When block 33 is advanced over the groove 34 by rotation of lead screw 36, the block 33 clamps the wire lead in the groove 34 in the same manner as above-described with reference to FIGS. 1 6.

FIG. 9 shows a modified for-m terminal assembly similar to that shown in FIGS. 1-6. Instead of a thin base plate, the base 1t) of FlG. 9 is a block having a hole 18 formed therein at the base of the tapered V groove 12. The cap member 11 is also modified, in that it is shown as an elongate rectangular lbar instead of the oval of FIGS. 1-6 and the circles of FIG. 7. The hole 18 is for the purpose of facilitating the location `of the end of the wire lead. Instead of laying the lead directly in groove 12, the lead is fed downwardly into hole 18. When the cap lbar 11 is pivoted and passes over the hole, the lead is bent and laid in the groove 12 by the cap bar, being guided therein by the tapering sides of groove 12, and the cap bar is advanced thereover to clamp the lead in the groove 12 in the same manner as described with reference to FIGS. 1-6. This embodiment is contemplated as particularly useful for miniature connectors where the laying of a lead directly in the groove 12 would be arduous.

There has thus been presented several illustrative embodiments `of the invention. It will be appreciated that common to all these embodiments is the uniting of two connector members in surface engagement for movement of the surface of one member over the surface of the other. One of these surfaces is provided with a groove that tapers Iboth in depth and breadth from a base to an apex, and the other of these members is located and mounted to be moved over the groove to expose a greater or lesser portion thereof. In so doing said other member functions to clamp a wire lead placed in said groove, forming a maxi-mum cincture in the wire with the leading edge of said other element, and a lesser compression of the wire along a portion of its axial length.

Other embodiments of the invention, and various `modications and variations of those herein described will be apparent to those skilled in the art. For example, in the embodiments of FIGS. l, 7 and 9 the leading edge of the cap members may be shaped with a curvature such that at all times during the traverse of the leading edge over the groove the leading edge is orthogonal to the axial center line of the groove. Also in these embodiments, the groove may be made arcuate about the center of pivot of the cap member in order to facilitate said orthogonal relationship. It is further suggested that, if desired, in FIG. 8 the under surface of the block 33 (i.e., the surface that passes over the groove 14) may have a similar tapered groove therein oriented with its apeX pointing in the opposite direction from groove 34. With this arrangement the combined loverlapped cross-sectional area and volume of the two grooves diminishes as the block 33 passes over the groove 3d, until the Wire is clamped therebetween. This same approach can be used with the embodiments of FIGS. 1, 7 and 9 with the two oppositely pointing grooves formed to lie in arcs around the cap pivot point as a center. Accordingly, it is not contemplated that the invention be construed as limited to the described embodiments or their particular details, and such embodiments, variations, and modilications as are embraced by the spirit and scope of the appended claims are contemplated as within the purview of the present invention.

What is claimed is:

1. A connector comprising a rst element and a second element, each of said elements having substantially at juxtaposed surfaces, and means mounting said two elements for pivotal movement of one of said surfaces over the other of said surfaces, one of said elements having a groove formed in its said surface, said groove tapering in both depth and breadth along an axis extending generally along said surface of said one element, said other element having a leading edge portion formed to span the breadth of said tapered groove transverse to said axis at least over a portion of the length of said axis in the direction of from the -base to the apex of the groove and to traverse at least a portion of said groove along said axis on movement of said two surfaces relative to each other.

2. A connector as set forth in claim 1, wherein said portion of the length of said axis includes the apex of the groove.

3. A connector comprising a base member having a substantially flat surface, a cap member having a substantially flat surface overlying and contacting said base member surface, a pivot pin means securing said two members together for relative pivotal movement of one said surface over the other, said cap member surface Vhaving a leading edge, said base member having a groove formed in its said surface tapering in both breadth and depth along an axis extending generally along said base memer surface, at least a portion of said groove lying in the path of pivotal movement of said cap member surface relative to said base member surface, said leading edge traversing said groove along said axis over said portion in the direction of from the base to the apex of the groove, said leading edge spanning the breadth of said groove over said portion.

4. A connector as set forth in claim 3, wherein said leading edge is curvilinear.

5. A connector as set forth in claim 3, wherein said leading edge is rectilinear.

6. A connector as set forth in claim 3, wherein said base member has a hole formed in said base member surface adjacent the base end of said tapered groove.

7. A connector as set forth in claim 3, wherein said base member has a plurality of said tapered grooves, and a said cap member is associated with each yof said grooves.

8. A connector as set forth in claim 3, wherein said portion of said groove includes the apex of the groove.

References Cited by the Examiner UNITED STATES PATENTS 940,397 ll/l909 Lungen. 1,781,680 11/1930 Ring. 24--136 2,768,363 10/1956 Haynes 339-270 2,771,295 11/1956 Andres 339-273 X 2,946,036 7/1960 Bettencourt 339-95 3,140,909 7/1964 Danesi 339--249 FOREIGN PATENTS 16,854 1899 Great Britain.

JOSEPH D. SEERS, Primary Examiner.

W. DONALD MILLER, Examiner. 

1. A CONNECTOR COMPRISING A BASE MEMBER HAVING A SUBSTANTIALLY FLAT SURFACE, CAP MEMBER HAVING A SUBSTANTIALLY FLAT SURFACE OVERLYING AND CONTACTING SAID BASE MEMBER SURFACE, A PIVOT PIN MEANS SECURING SAID TWO MEMBERS TOGETHER FOR RELATIVE PIVOTAL MOVEMENT OF ONE SAID SURFACE OVER THE OTHER, SAID CAP MEMBER SURFACE HAVING A LEADING EDGE, SAID BASE MEMBER HAVING A GROOVE FORMED IN ITS SAID SURFACE TAPERING IN BOTH BREADTH AND DEPTH ALONG AN AXIS EXTENDING GENERALLY ALONG SAID BASE MEMBER SURFACE, AT LEAST A PORTION OF SAID GROOVE LYING IN THE PATH OF PIVOTAL MOVEMENT OF SAID CAP MEMBER SURFACE RELATIVE TO SAID BASE MEMBER SURFACE, SAID LEADING EDGE TRAVERSING SAID GROOVE ALONG SAID AXIS OVER SAID PORTION IN THE DIRECTION OF FROM THE BASE OF THE APEX OF THE GROOVE, SAID LEADING EDGE SPANNING THE BREADTH OF SAID GROOVE OVER SAID PORTION. 